Washington: US President Barack Obama has kept open all options to prevent Iran from acquiring nuclear weapons, but believes that the window of diplomacy remains open to achieve this objective, the White House said on Monday.

White House Press Secretary Jay Carney told reporters that there was "absolutely no daylight between the United States and Israel when it comes to the necessity of preventing Iran from acquiring a nuclear weapon."

President Obama "has been engaged in a policy that has put enormous pressure on the regime in Tehran, isolated it and sanctioned it to a degree that is unprecedented," he added.

Carney said Obama has made clear that in pursuit of the objective of preventing Iran from acquiring a nuclear weapon, "all options remain on the table."

"It is the case that the window for diplomacy remains open, and it remains the case that the best way to ensure that Iran does not acquire a nuclear weapon is through a diplomatic process that results in Iran finally agreeing to, in a completely verifiable way, give up its nuclear weapons ambitions and abide by its international obligations."

He, however, warned that the "window will not remain open indefinitely." The West suspects Iran is pursuing a nuclear weapons programme, a charge denied by Tehran.

"I think everyone here who has been covering these issues for the past four years has seen clearly is a change in the way the world views this problem. When President Obama was running for this office, and when he took this office in January of 2009, the world was divided over this issue of Iran's nuclear ambitions, and Iran was united," he said.

"Thanks to the President's policy and the pursuit of it, the world has united and come to a consensus that is unprecedented, in agreement that Iran is the problem; that it is Iran's failure to live up to its international obligations that has caused this situation that is of such serious concern to President Obama, obviously to Prime Minister Netanyahu, and to leaders around the region and around the world," he said.

"I think it is a testament to the vision that the President had when he when he ran for the office, that he understood the value in uniting the international community behind a plan of action that has isolated Iran, put enormous financial stress and political pressure on Iran as we pursue this goal of preventing Iran from acquiring a nuclear weapon," Carney said.